Notes on Brewing

Random notes are kept here on various topics available for reading until I get to arrange them in to proper reading and training material.

Diatoms

A glass-like cell wall is a unique characteristic of diatoms
another group of unicellular algae (from the group known as Protista). A diatom's cell wall contains
silica, the same mineral that makes up glass. These rigid cell walls
give diatoms a variety of geometric shapes. The cell wall consists of
two halves that fit together like the bottom and lid of a shoebox.
Diatoms contain chlorophyll, but appear yellow or brown because they
also contain other pigments that mask the green colour. Both freshwater
and marine environments are rich in diatoms, which are key members of
plankton. They are as important a food source for many marine animals as
grasses are for many land animals.

Diatoms store their food reserves in the form of an oil, which
enables them to float near the surface where they are exposed to
sunlight. When diatoms die, they no longer produce this oil, and they
sink to the ocean floor. The glassy cell walls do not decompose and,
over time, they accumulate and can become fossilised. Enormous numbers
of fossilised diatoms make up thick sediments known as diatomaceous earth. This soil is mined for use as a filter material,
as a grinding and polishing agent, and as an ingredient in some
toothpastes.